Metal-semiconductor Janus nanostructures with asymmetry and directionality have recently aroused significant interest,both in fundamental light-matter interactions mechanism and in technological applications.Here we report the synthesis of different Au-ZnO Janus nanostructures via a facile one-pot colloid method.The growth mechanism is revealed by a series of designed synthesis experiments.The light absorption properties are determined by both the decrease of dipole oscillations of the free electrons and the plasmon-induced hot-electron transfer.Moreover,the finite-difference time-domain (FDTD) simulation method is used to elucidate the electric field distributions of these Janus nanostructures.